mutter: Add a virtual monitor by default
Of all Wayland compositors supported, the mutter based ones (either mutter or gnome-kiosk) and the only ones not creating a virtual monitor by default.
Check if no virtual monitor was specified from the command line, and if there's none, add a virtual 1024x768 monitor by default to mimic what other compositors do, since some applications expect to have at least one wl_output and would fail without one.
Signed-off-by: Olivier Fourdan ofourdan@redhat.com
Edited by Olivier Fourdan